Protonation of carbene-stabilized diphosphorus: complexation of HP2+

Abstract

Reaction of carbene-stabilized diphosphorus, L:P–P:L (5) (L: = :C{N(2,6-Prⁱ₂C₆H₃)CH}₂) with pyridine hydrochloride yields [L:(H)P–P:L]Cl (6), a salt containing the HP₂⁺ cation—the elusive phosphorus analogue of the well known diazonium cation, HN₂⁺. In addition to reporting the synthesis and structure, the nature of (6) was further probed by DFT computations. Interestingly, carbenes may be employed to deprotonate (6), affording the starting material (5).